This invention relates to a device for supplying a piece preformed of synthetic resin to the next processing line in an apparatus for producing a bottle-shaped blow-molded container of biaxially oriented synthetic resin.
In molding a bottle-shaped container of synthetic resin such as polyethylene terephthalate resin by means of an injection blow molding process, there is adopted an orientation blow molding process which has the steps of first molding a cylindrical piece with a bottom as preformed piece by an injection molding machine, heating the piece to predetermined temperature, charging it into a mold, and biaxially orientation blow molding the piece to thus produce a final product. In order to increase the number of the products such as bottle-shaped containers to be molded per unit time in this case, the conventional process employs the steps of engaging the preformed primary piece with predetermined jig to load the preformed piece in the jig, and passing the preformed piece jig assembly through a heater and a biaxially orientation blow molding machine as it is in case of forming a bottle-shaped secondary container or product.
Generally, since there is a molding temperature difference between injection molding and a blow molding, a preformed primary piece injection molded is cooled to predetermined temperature while being supplied to a blow molding machine and is reheated to predetermined temperature prior to a blow molding.
A number of pieces are simultaneously injection-molded, since they are relatively small in size, in an injection molding machine, and are conveyed via a belt conveyor or the like in random, uncontrolled position. However, it is very preferably to convey the pieces thus preformed to a blow molding machine if the pieces are engaged at their projected peripheries at the neck portions thereof to become ports of bottle-shaped containers in upward neck portion attitude.
To this end, the pieces to be conveyed to a blow molding machine should be engaged with orienting jigs disposed upside down due to molding process in neck portion downward position.